We fly thousands of miles, dumping about 15 extra tons of CO2 into the atmosphere as a class of 20, clambering onto a boat that spews gasoline fumes to see an ecosystem threatened primarily by increasing temperatures from climate change. Human activity. Tourism. Industry. Agriculture.

We all have to eat. But we don’t all have to get on airplanes for education or vacations.

Here we are, anyway, chugging our way out on the Goliath to Tuffy Reef, less than 45 minutes from the shore on Ambergris Caye, Belize. The setting sun in a ferocious blaze of pink and orange behind us mixes its unrelenting heat with the breeze that cools our sweaty backs.

Dr. Ken said when we arrived that he thought the reef would be gone in our lifetime. He’s spent decades studying, researching, and educating students about an ecosystem that is disappearing in front of his eyes. The elkhorn crumbles from disease. The colorful fans fade away one wave at a time. The nematocysts blink out with the coral. The angelfish, nurse sharks, eagle rays, and manatees sink into the obscurity of the fossil record. We watch it happen.

We are complicit in the end. No innocence on the reef.

Dr. Ken gives us the briefing, describing what we’re likely to see at night under the waves. What we should look for. Where we’re going. His talk is longer than normal. I think he’s stalling as we digest pizza. He wants to give us a break between dinner and the inevitable blackness that awaits, but he also wants the sun to fully set.

Our group stumbles around in the dark in the cramped confines of Goliath, stowing our backpacks and shoes in the unlit cabin, debating whether we’re going to wear our rash guards. One by one, students fit on their fins and masks, acquire their torches, and drop into the water in pairs. A handful of students depart with a guide.

Another group leaves. Five of us and Ken are left.

I sit on the dive platform at the back of the boat, ready to swim, contemplating the darkness below. It has been more than two decades since I’ve entered the ocean at night, and that childhood moment was never in such wondrous circumstances as these.

Fear trickles in dribs and drabs from my amygdala to my groin as I contemplate the plunge. I remain silent as our mutual nervousness settles between my partner and I.

I drop off the platform feet first, hand pressing against my mask. Blackness closes around in a lukewarm embrace. I am frantic with my light, shining it around and under the boat. There is nothing here that is dangerous to me -- the largest predator out here, a nurse shark, is neither aggressive nor interested in humans. We have seen several in the last few days. During the daylight, they are fascinating, regal, smooth.

At night, I scare myself when I bump my fin against my own leg, or feel the prickled touch of harmless sargassum against my neck.

I gulp air through the snorkel and remind myself to relax my jaw. Tension radiates in cords from my throat through my chest.

Panic settles to a dull roar from that wild first flare-up. Our group leaves the dubious safety of the boat, torches cutting thin lines of light to the white sand 30 feet below. When Ken sees an animal of interest, he waves his light over it like a disco strobe.

We hand around a West Indian sea egg someone plucked off the bottom. Its soft white spines tickle my palm. It squishes and sucks onto my hand, a warm, gelatinous lump with primitive motivations.

Someone spots a tiny, translucent squid. We form a circle around it, shining our lights towards the center, bumping shoulders and fins and blinding each other as we try to stay in place, trapping it in the light.

I hold up my arm underneath. Jets of water and a soft slickness push against my skin. It darts straight for my face, purple-tinged eyes boring into mine. I redirect it back towards the center with a gentle hand. When it inks a cloudy purple jet, we break the circle. It darts away with a good story for the pub, unharmed.

We swim on, sticking close together. The sargassum packs around us on the surface, scratchy and ominous. In desperation, I dive underneath only to pop up, out of air, still in the middle of the patch. I give up and swim through, picking off small pieces caught on my neck and ankles every few minutes.

We pull up in front of a reef wall in a line, the six of us small bobbing heads under the distant sky. The lights from shore are far enough out that the Milky Way shines through in a way I haven’t seen since I was a child in the mountains. Jupiter glints low on the horizon.

“Out the lights!” calls Ken. A tremor runs through the group.

I flip off the switch. Others follow. The coral’s bright pinks and purples turn black. I reach out and grasp my partner’s upper arm. Someone else on my right grips my forearm. We wait. Ninety seconds in the dark ocean, Ken said on the boat, is sometimes too much for some people. We persevere. I am proud of our group.

The reef glows in its glorious bioluminescent display. The flecks of glowing, glittering green scattered over the coral waver under the surface. I divide my mask at the water line. Stars above reel into stars below with each rising wave. Two worlds both wholly foreign to me. One, a place fading into memory even now. The other, too far out of reach for the dreams of our frail species. Our satellites will outlast our civilization.

We turn the lights on again and begin to meander back towards the boat. I hang back from the others and “out my light” again and again until my nerves force me to switch it on and catch up with the group.

In the darkness, alone, embraced in the ocean, I can See.